From: "Eugenio Pérez" <eperezma@redhat.com>
To: qemu-devel@nongnu.org, Peter Xu <peterx@redhat.com>,
"Michael S. Tsirkin" <mst@redhat.com>
Cc: "Peter Maydell" <peter.maydell@linaro.org>,
"Aleksandar Rikalo" <aleksandar.rikalo@syrmia.com>,
"Yan Zhao" <yan.y.zhao@intel.com>,
"Eduardo Habkost" <ehabkost@redhat.com>,
"Juan Quintela" <quintela@redhat.com>,
qemu-ppc@nongnu.org, "Jason Wang" <jasowang@redhat.com>,
"Eric Auger" <eric.auger@redhat.com>,
qemu-arm@nongnu.org, "Hervé Poussineau" <hpoussin@reactos.org>,
"Avi Kivity" <avi@redhat.com>,
"Paolo Bonzini" <pbonzini@redhat.com>,
"Richard Henderson" <rth@twiddle.net>,
"David Gibson" <david@gibson.dropbear.id.au>
Subject: [PATCH v2 4/5] intel_iommu: Skip page walking on device iotlb invalidations
Date: Mon, 19 Oct 2020 12:43:31 +0200 [thread overview]
Message-ID: <20201019104332.22033-5-eperezma@redhat.com> (raw)
In-Reply-To: <20201019104332.22033-1-eperezma@redhat.com>
Although they didn't reach the notifier because of the filtering in
memory_region_notify_iommu_one, the vt-d was still splitting huge
memory invalidations in chunks. Skipping it.
This improves performance in case of netperf with vhost-net:
* TCP_STREAM: From 1923.6Mbit/s to 2175.13Mbit/s (13%)
* TCP_RR: From 8464.73 trans/s to 8932.703333 trans/s (5.5%)
* UDP_RR: From 8562.08 trans/s to 9005.62/s (5.1%)
* UDP_STREAM: No change observed (insignificant 0.1% improvement)
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
hw/i386/intel_iommu.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/hw/i386/intel_iommu.c b/hw/i386/intel_iommu.c
index 6cc217742a..8f1ac137a6 100644
--- a/hw/i386/intel_iommu.c
+++ b/hw/i386/intel_iommu.c
@@ -1478,6 +1478,10 @@ static int vtd_sync_shadow_page_table(VTDAddressSpace *vtd_as)
VTDContextEntry ce;
IOMMUNotifier *n;
+ if (!(vtd_as->iommu.iommu_notify_flags & IOMMU_NOTIFIER_IOTLB_EVENTS)) {
+ return 0;
+ }
+
ret = vtd_dev_to_context_entry(vtd_as->iommu_state,
pci_bus_num(vtd_as->bus),
vtd_as->devfn, &ce);
--
2.18.1
next prev parent reply other threads:[~2020-10-19 10:54 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-19 10:43 [PATCH v2 0/5] memory: Skip assertion in memory_region_unregister_iommu_notifier Eugenio Pérez
2020-10-19 10:43 ` [PATCH v2 1/5] memory: Rename memory_region_notify_one to memory_region_notify_iommu_one Eugenio Pérez
2020-10-19 10:43 ` [PATCH v2 2/5] memory: Add IOMMUTLBEvent Eugenio Pérez
2020-10-30 10:49 ` Michael S. Tsirkin
2020-11-16 17:03 ` Eugenio Perez Martin
2020-10-19 10:43 ` [PATCH v2 3/5] memory: Add IOMMU_NOTIFIER_DEVIOTLB_UNMAP IOMMUTLBNotificationType Eugenio Pérez
2020-10-19 10:43 ` Eugenio Pérez [this message]
2020-10-19 10:43 ` [PATCH v2 5/5] memory: Skip bad range assertion if notifier is DEVIOTLB_UNMAP type Eugenio Pérez
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20201019104332.22033-5-eperezma@redhat.com \
--to=eperezma@redhat.com \
--cc=aleksandar.rikalo@syrmia.com \
--cc=avi@redhat.com \
--cc=david@gibson.dropbear.id.au \
--cc=ehabkost@redhat.com \
--cc=eric.auger@redhat.com \
--cc=hpoussin@reactos.org \
--cc=jasowang@redhat.com \
--cc=mst@redhat.com \
--cc=pbonzini@redhat.com \
--cc=peter.maydell@linaro.org \
--cc=peterx@redhat.com \
--cc=qemu-arm@nongnu.org \
--cc=qemu-devel@nongnu.org \
--cc=qemu-ppc@nongnu.org \
--cc=quintela@redhat.com \
--cc=rth@twiddle.net \
--cc=yan.y.zhao@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).